From 1f5d4699862afee1e410fcb0e1f5e751ebcd2f9f Mon Sep 17 00:00:00 2001
From: Damien Arrachequesne <damien.arrachequesne@gmail.com>
Date: Tue, 2 Feb 2021 10:27:30 +0100
Subject: [PATCH] fix: do not reset the ping timer after upgrade

There was two issues with this behavior:

- v3 clients (with allowEIO3: true) were also receiving a "ping" after
a successful upgrade, which is incorrect (in v3, it's the client that
sends the "ping", and the server answers with a "pong")

- the ping timer is not reset after upgrade on the client-side, so an
upgrade which took longer than the `pingTimeout` duration could lead to
a "ping timeout" error on the client-side

I think the latter issue is present since the initial implementation.

Related: https://github.com/socketio/socket.io-client-swift/pull/1309#issuecomment-768475704

Backported from https://github.com/socketio/engine.io/commit/ff2b8aba48ebcb0de5626d3b76fddc94c398395f
---
 lib/socket.js  |  1 -
 test/server.js | 18 ++++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/lib/socket.js b/lib/socket.js
index 177b25c69..376e3c1d7 100644
--- a/lib/socket.js
+++ b/lib/socket.js
@@ -208,7 +208,6 @@ Socket.prototype.maybeUpgrade = function (transport) {
       self.clearTransport();
       self.setTransport(transport);
       self.emit('upgrade', transport);
-      self.setPingTimeout();
       self.flush();
       if (self.readyState === 'closing') {
         transport.close(function () {
diff --git a/test/server.js b/test/server.js
index d34f2f235..4954f8ca3 100644
--- a/test/server.js
+++ b/test/server.js
@@ -1092,6 +1092,24 @@ describe('server', function () {
       });
     });
 
+    it('should not timeout after an upgrade', done => {
+      const opts = { pingInterval: 200, pingTimeout: 20 };
+      const engine = listen(opts, port => {
+        const socket = new eioc.Socket('ws://localhost:%d'.s(port));
+        socket.on('open', () => {
+          setTimeout(() => {
+            socket.removeListener('close');
+            engine.close();
+            socket.close();
+            done();
+          }, 500);
+        });
+        socket.on('close', () => {
+          done(new Error('should not happen'));
+        });
+      });
+    });
+
     it('should not crash when messing with Object prototype', function (done) {
       Object.prototype.foo = 'bar'; // eslint-disable-line no-extend-native
       var engine = listen({ allowUpgrades: true }, function (port) {